High Occupancy Vehicle (HOV) lane enforcement is one of the important topics in the transportation management business. In HOV lane enforcement, penalties are imposed on owners of vehicles travelling with less than a predetermined number of occupants (e.g., less than 2). Recent efforts have been directed to the areas of sensing and image capture for HOV lane enforcement. Further development in this art is needed as entirely automatic solutions for determining the number of occupants in a vehicle can be quite challenging, particularly for the passengers in the back seats. Nevertheless, semi-automatic methods that combine machine detection with human verification/inspection are valuable, as these methods reduce the workload and increase the detection rate comparing to entirely human detection. In the semi-automatic method, an alert signal, together with images/video of the vehicle, is sent to the law-enforcement officer, if an HOV lane violation is detected by the machine. The officer may verify the captured image and decide if further actions are necessary. Such methods increase the productivity of the traffic enforcement authorities.
Accordingly, what is needed in this art are increasingly sophisticated systems and methods for processing an image of a motor vehicle to determine whether a front seat in a front passenger compartment of that vehicle is occupied.